The field of the invention relates generally to aircraft control systems and, more particularly to methods and systems for enhanced control of a vertical tail of an aircraft.
At least some known vehicles capable of flight include one or more vertical tails to provide directional control for the vehicle. For example, at least some known aircraft include one or more vertical tails that include a stabilizer and a rudder. In such aircraft, the vertical tail provides yaw control of the aircraft.
At least some known aircraft must be designed to compensate for an unbalanced yaw moment during certain operating conditions. For example, at least some multi-engine aircraft experience an unbalanced yaw moment during a one-engine inoperative (OEI) condition. During an OEI condition, one engine malfunctions such that operation of the remaining engine may induce rotation of the aircraft about a yaw axis in a rotational direction towards the inoperative engine. At least some of such known aircraft compensate for unbalanced yaw moment using a vertical tail.
Generally, the size of a vertical tail is determined by the amount of directional control that is required for an aircraft. Furthermore, the drag of an aircraft during flight is dependent on the size of the vertical tail. For example, a larger vertical tail results in increased drag of the aircraft. Drag increases the fuel consumption and limits the distance an aircraft can travel without refueling. Moreover, when an aircraft operates at a low velocity, the vertical tail has a decreased amount of control over the aircraft when compared to when the aircraft operates at a high velocity. For example, a large vertical tail is required to provide sufficient directional control of an aircraft during an OEI condition when the aircraft is operating at a low velocity. As such, it may be desirable to augment tail control authority to compensate for an OEI condition during takeoff and enable the use of a reduced size vertical tail.